Cerebral capillary endothelial cultures. II. Adenylate cyclase response to prostaglandins and their interactions with the adrenergic system. The response of endothelial adenylate cyclase (AC) to prostaglandins (PGE1, PGE2, PGF1Alpha , PGF2Alpha , PGD2 and PGI2) and the relationship of PGE2 to adrenergic systems were investigated in cerebrovascular endothelia cultures. E-type prostaglandins and PGI2 were more effective in stimulating endothelial AC (EC50 = 3 x 10 to the -7M, and 3 x 10 to the -6M, respectively) than prostaglandins of the F-series and PGD2 which activated AC at high doses only. A modulation of endothelial AC response to either PGE2 or norepinephrine (NE) was observed in the presence of both agents in the system. It was manifested by a dose-dependent NE inhitition of the PGE2-stimulated formation of cAMP, which was partially restored by phentolamine. Alpha and Beta-adrenergic agonists (Alpha, clonidine and 6-fluoronorepinephrine; and Beta, isoproterenol) also partly blocked while forskolin and PGE2 synergistically stimulated the production of cAMP in the endothelial cultures. These findings strongly suggest that the interaction of prostaglandins and Alpha- and Beta-adrenergic agonists with the AC system in cerbrovascular endothelium may play a role in the regulation of the cerebral microcirculation and/or blood pressure.